Proline is a non-essential amino acid. Therefore, the body is capable of synthesizing the amino acid from the non-essential amino acid glutamate. Consequently, it is not necessary to obtain proline through dietary sources.

The amino acid is a component of various biological molecules and structures in the body, and it is of crucial importance due to its structure and function. Proline is known as a "helix breaker," meaning it disrupts the formation of the typical spiral structure, called α-helix, in proteins. As a result, proline contributes to the variability of protein structures and enables their functional diversity.

One of the main functions of proline is to provide structural integrity and stability to proteins and connective tissues. It plays a crucial role in the formation and maintenance of collagen, the main component of connective tissue that surrounds the skin, bones, tendons, cartilage, and blood vessels. Proline helps strengthen the structure of collagen, making it more resistant to stress.

What Is The Difference Between Proline And L-Proline?

L-proline and proline are the same chemical molecule. The term proline is often used synonymously with L-proline since the L form is the most common and biologically relevant form. The letter L before proline indicates the L-form of the molecule. L-proline is the naturally occurring form of proline, while there is also a mirror image form known as D-proline. In biochemistry, the L and D forms of amino acids are used to describe the stereochemistry of the molecules. However, when specifically referring to the D form of proline, it is usually indicated to avoid misunderstandings.

Higher Requirements?

In terms of requirements, there isn't much to consider as proline can be synthesized from other amino acids. The body's own production can usually meet the demand. A balanced diet that includes a variety of protein sources typically suffices to meet the requirement. However, in certain cases, it may be beneficial to ensure an adequate intake of proline:

  • An increased need may occur in individuals engaged in intense physical training or athletic activity, as protein breakdown is increased during exercise.
  • Specific protein requirements may arise in individuals with certain conditions such as liver diseases or inherited metabolic disorders, which can also affect proline needs.
  • Individuals who are injured, have wounds, or are in a postoperative state may have an increased need, as proline plays a significant role in injury healing and tissue regeneration.

Proline-Rich Foods

There is a variety of vegan foods that contain proline. The following list provides good options based on food groups:

  • Legumes such as lentils, chickpeas, black beans, kidney beans, white beans, green peas, soybeans, peanuts, lima beans, and adzuki beans are protein-rich foods that also contain high amounts of proline. Soy products like tofu, tempeh, edamame, soy yogurt, soy flour, miso, and soy protein isolate should also be considered as they have high proline content. Here is the table showing proline content in legumes.
  • Whole grains and grain products are rich in proline. Oats, quinoa, brown rice, amaranth, barley, buckwheat, millet, spelt, and rye are excellent sources of fiber and proline.
  • Nuts and seeds are good sources of proline. According to the table, almonds, cashews, walnuts, hazelnuts, sunflower seeds, chia seeds, flaxseeds, hemp seeds, sesame seeds, and pumpkin seeds are rich in healthy fats, proteins, and proline.
  • Vegetables have a moderate proline content. Examples include broccoli, spinach, savoy cabbage, lamb's lettuce, kale, shallots, asparagus, leeks, and red cabbage. Use this table for proline content in vegetables.
  • Algae such as nori, wakame, kombu, and dulse are also proline-rich foods. They can be used in sushi rolls, soups, or salads.
  • Fruits contain less proline compared to protein-rich foods like legumes or nuts. However, there are some fruits like apricots, avocados, grapes, persimmons, mandarins, oranges, and kiwis that offer a low proline content. Dried fruits should not be overlooked either. The drying process removes water from the fruits, making them more shelf-stable and leaving behind a concentrated nutrient content. Good examples of dried fruits with higher proline content include goji berries, raisins, dates, figs, and coconut meat.

Vegan Proline Diet

How to incorporate proline into your diet is shown in the following list of vegan recipe ideas that include proline-rich foods as ingredients:

  • Quinoa salad with black beans, avocado, and cilantro: Combine cooked quinoa with black beans, fresh avocado, and chopped cilantro.
  • Lentil dal with spinach and coconut milk: Cook red or green lentils with spinach, spices, and coconut milk to make a protein-rich dal.
  • Nut butter smoothie with chia seeds: Blend a mixture of nut butter (such as almond butter), banana, plant milk, and chia seeds.
  • Vegan bean burgers: Prepare hearty burger patties using mashed beans, oats, and spices, and serve them on whole grain buns.
  • Tofu scramble with vegetables: Sauté diced tofu with onions, bell peppers, and spinach.
  • Vegan chili sin carne: Cook a savory mixture of beans, soy granules, bell peppers, onions, and spices.
  • Vegan protein pancakes: Make delicious pancakes using protein-rich flour like oat or chickpea flour, and serve them with fresh fruit and nut butter.
  • Vegan pasta with creamy cashew sauce: Blend soaked cashews with plant milk, nutritional yeast, and spices to create a creamy sauce, and serve it over pasta.
  • Vegan sushi rolls with vegetables and tofu: Roll fresh vegetables, marinated tofu, and avocado in nori seaweed sheets.
  • Quinoa tabbouleh with fresh herbs: Mix cooked quinoa with fresh herbs like parsley, mint, and spring onions.
  • Vegan protein bars with nuts and seeds: Make your own protein bars by combining a mixture of nuts, seeds, dried fruits, and oats.